AbstractCurrent research in attitudes towards the sexuality of adults with intellectual disabilities yields heterogeneous results. The aim of the present paper was to systematically review current qualitative and quantitative evidence of attitudes towards the sexuality of adults with intellectual disabilities. A systematic review of current literature (2000–2020) was carried out in the ERIC, PsychINFO, SCOPUS, PUBMED, and WebOfScience databases. Thirty-three articles were included for review. The present review protocol is registered in the PROSPERO database. Included studies presented attitudes towards the sexuality of adults with intellectual disabilities in samples comprised of staff, family, members of the community, and adults with intellectual disability. Community samples held more positive attitudes, followed by staff and family. Adults with intellectual disabilities reported interest in intimate relationships but perceived barriers in others’ attitudes. Factors such as familiarity, age, gender of the adult with a disability, and culture seemed to have clear relationships. Other factors such as gender or social status remain unclear. In general, attitudes were considered positive. However, a preference for low intimacy and friendship or Platonic relationships was found. Stereotypes towards intellectual disability may have a strong influence. These findings underline the need to investigate and address attitudinal changes to provide adequate support for adults with intellectual disabilities in regard to a healthy relational and sex life.Prospero registration number: CRD42021222918.